1. Field of the Invention
The invention is directed to vehicle control systems, and more particularly, to a crawler motion control system which can control the direction, speed and steering of a crawler from a single joystick control. It will be understood that the system is not limited solely to crawlers, and may have application to other types of vehicles, including bulldozers and excavators, and other vehicles having tracks.
2. Background Art
Systems for controlling the movement of crawlers or other tracked construction or heavy equipment has long been known in the art. Generally, such systems are designed so that the driver of such a vehicle is required to use two hands to execute maneuvers. In other situations, a single hand can be used to operate the system, however, it becomes necessary for the user to grab several different control device, such as several joysticks. Such controls require great expertise, and repeated use tends to tire a user.
Still other solutions have placed all such controls on a single joystick. While these solutions have been advances that have attempted to address the shortcomings of the multiple control devices, these solutions have nevertheless suffered from several drawbacks. Specifically, many of these systems are exceedingly complicated. As a result, the production cost is excessive. Furthermore, since these systems require a multitude of custom components and tight tolerances, the reliability of such systems suffers.
Accordingly, it is an object of the invention to develop a single control system for controlling the motion of a crawler.
It is an additional object of the invention to simplify the components necessary for a control system so as to increase the reliability of same.
It is a further object of the invention to minimize the cost associated with the production of a single control system for a crawler.
These and other objects will become apparent in light of the specification and claims appended hereto.
The invention comprises, in part, a motion control system for controlling the motion of a crawler having a left and right track. In one aspect, the system comprises a pivotally mounted controller, steering control means and direction control means. The steering control means is hydraulically communicable with a pressurized fluid supply, a brake of each of a left and right track of a crawler and a clutch of each of a left and right track of a crawler. The direction control means hydraulically communicable with a pressurized fluid supply, a forward and a reverse transmission signal input. The steering control means is positioned so that pivoting the controller in a first series of planes operates the steering control means and pivoting the controller in a second series of planes operates the direction control means.
In a preferred embodiment, the steering control means further comprises a first and a second steering valve. The first steering valve is hydraulically communicable with a pressurized fluid supply, a clutch and brake of the right track of a crawler. The second steering valve is hydraulically communicable with a pressurized fluid supply, a clutch and brake of the left track of a crawler. Pivoting the controller in a first series of planes moves one of the first and second steering valves relative to a respective casing, to, in turn, alter the hydraulic communication between a respective pressurized fluid supply and a respective clutch and brake.
In a preferred embodiment, the first steering valve is hydraulically communicable with a right clutch of the crawler, to, in turn, facilitate the selective disengagement of a high clutch setting for the right clutch. In another preferred embodiment, the second steering valve is hydraulically communicable with a left clutch of the crawler, to, in turn, facilitate the selective disengagement of a high clutch setting for the left clutch.
In another preferred embodiment, the first steering valve and the second steering valve are substantially identical.
Preferably, the direction control means further comprises a forward valve hydraulically communicable with a pressurized fluid supply and a forward transmission signal input and a reverse valve hydraulically communicable with a pressurized fluid supply and a reverse transmission signal input. Pivoting the controller in a second series of planes moves one of the forward and reverse valve relative to a respective casing, to, in turn, hydraulically communicate a pressurized fluid supply with one of a forward or reverse transmission signal input.
In a preferred embodiment, the forward valve includes a hydraulic lock member, to, in turn, utilize fluid from a pressurized fluid supply to maintain the forward valve in an engaged position. In another embodiment, the reverse valve includes a hydraulic lock member, to, in turn, utilize fluid from a pressurized fluid supply to maintain the rearward valve in an engaged position.
In another preferred embodiment, the motion control system further comprises means for controlling the steering speed of a left track and a right track. In one such embodiment, the motion control system includes at least one selector associated with the controller. In another such embodiment, the at least one selector comprises a left gear switch associated with a left clutch, the left gear switch having at least two settings and a right gear switch associated with a right clutch, the left gear switch having at least two settings.
In yet another preferred embodiment, the motion control system further comprises means for controlling the transmission gears. Preferably, the transmission gear control means includes at least one transmission selector member associated with the controller.
In another aspect of the invention, the invention comprises a motion control system for controlling the motion of a crawler having a left and right track. The system comprises a pivotally mounted controller, steering control means hydraulically communicable with a pressurized fluid supply, a brake of each of a left and right track of a crawler and a clutch of each of a left and right track of a crawler, direction control means hydraulically communicable with a pressurized fluid supply, a forward and a reverse transmission signal input, means for controlling the steering speed of a left track and a right track, the steering speed controlling means having at least one selector, and means for controlling the transmission gears, the transmission gear controlling means having at least one transmission gear selector. In such an aspect of the invention, the steering control means is positioned so that pivoting the controller in a first series of planes operates the steering control means. Similarly, pivoting the controller in a second series of planes operates the direction control means. Moreover, the at least one selector and the at least one transmission gear selector is associated with the controller.
The invention likewise comprises a method of controlling the motion of a crawler having a left and right track. The method comprises the steps of providing a pivotally mounted controller; selectively pivoting the controller along a first series of planes, wherein a pivot to the left directs the crawler to the left, and a pivot to the right directs the crawler to the right and selectively pivoting the controller along a second series of planes, wherein a pivot forward directs the crawler into a forward gear, and a pivot to the rear directs the crawler to the left.
In a preferred embodiment, the method further comprises the steps of providing at least one selector for each track on the controller and selectively manipulating at least one selector for at least one track to selectively engage one of at least two clutch settings. In one such embodiment, the method further comprises the steps of providing at least one transmission selector on the controller, and selectively manipulating the at least one transmission selector to selectively engage one of at least two transmission gears.